Journal of Radiation Protection and Research

The Korean Association for Radiation Protection (대한방사선방어학회)
권호 표지
DOI QR코드

DOI QR Code

The Review of Exposure Index in Digital Radiography and Image Quality

디지털 영상에서 화질관리에 관한 노출지수(EI)의 유용성 연구

  • Yang, Sook (Dept. of Radiology, Dongshin university) ;
  • Han, Jae Bok (Dept. of Radiology, Dongshin university) ;
  • Choi, Nam Gil (Dept. of Radiology, Dongshin university) ;
  • Lee, Seong Gil (Deprt. of Radiation Technology, Gwangju Health University)
  • 양숙 (동신대학교 방사선학과) ;
  • 한재복 (동신대학교 방사선학과) ;
  • 최남길 (동신대학교 방사선학과) ;
  • 이성길 (광주보건대학교 방사선과)
  • Received : 2012.12.24
  • Accepted : 2013.01.28
  • Published : 2013.03.30

Abstract

The aim of this study was to determine the correlation between exposure index (EI) and dose factors related to radiation dose optimization in digital radiography (DR) system. Two phantoms with built-in regional test object for quantitative assessment of images were used to produce image signals that acquired in chest radiography background. EI and entrane surface dose (ESD) increased proportionally with rise of radiation dose (kVp, mAs) in both DR and CR systems. Especially, DR detector was effective to form good contrast and hence, reached easily to improvement of image quality with minimal dose changes. It made operators possible to expect the accuracy of EI values deeply related to absorbed dose of the detector. The evaluation of images was obtained specially employed calculation of noise to signal ratio (NSR) and contrast to noise ratio (CNR). These measurements were performed for how exposure factors affect image quality. NSR was inversely proportional to kVp and mAs and low NSR represented high signal detection efficiency. Consequently, EI values was the measure of the amount of exposure received by the image receptor and it was proportional to exposure factors. Therefore the EI in a recommended range from manufacturer can offer optimal image quality. Also, continuous monitoring of EI values in the digital radiography can reduce the unnecessary patient dose and help the quality control of the system.

Keywords

File

Download PDF

Acknowledgement

Supported by : 동신대학교

References

  1. Vassileva J. A phantom for dose-image quality optimization in chest radiography. Brit. J. Radiol. 2002;75:837-842. https://doi.org/10.1259/bjr.75.898.750837
  2. Neitzel U. The exposure index and its standardization. PHILIPS. 2006.
  3. Busch HP, Faulkner K. Image quality and dose management in digital radiography: A new paradigm for optimisation. Radiat. Prot. Dosim. 2005;117:143-147. https://doi.org/10.1093/rpd/nci728
  4. Kotter E, Langer M. Digital radiography with large-area flat-panel detectors. Eur. Radiol. 2002;12:2562-2570. https://doi.org/10.1007/s00330-002-1350-1
  5. Lyra ME, Kordolaimi SD, Salvara AN. Presentation of digital radiographic systems and the quality control procedures that currently followed by various organizations worldwide. Recent Patents on Medical Imaging. 2006;2:5-21.
  6. Samei E, Ranger NT, Mackenzie A, Honey ID, Ravin CE. Effective DQE(eDQE) and speed of digital radiographic systems: An experimental methodology. Med. Phys. 2009;36:3801-3816.
  7. Shepard SJ, Flynn M. Calculation of the exposure index, American association of physicists in medicine. 2008:1-46.
  8. Bourne R. Fundamentals of digital imaging in medicine. Springer. 2009:87-134.
  9. Lee SC, Wang JN, Liu SC, Jiang SH. Evaluation of dose-image-quality optimization in digital chest radiography. Nucl. Instrum. Math. A. 2007:544-547.
  10. Shepard SJ, Wang J, Flynn M, Krugh K, Peck D, Samei E, Willis CE. An exposure indicator for digital radiography. AAPM. 2009;116:1-30.
  11. J. Anthony Seibert, Morin RL. The standarized exposure index for digital radiography: an opportunity for optimization of radiation dose to the pediatric population. Pediatr. Radiol. 2011;41: 573-581. https://doi.org/10.1007/s00247-010-1954-6
  12. Uffmann M, Cornelia S. Digital radiography: balance between image quality and required radiation dose. Eur. J. Radiol. 2009;72:202-208. https://doi.org/10.1016/j.ejrad.2009.05.060
  13. Fizik J. Correlation between objective and subjective image quality measures of medical radiographs. Jabatan Fizik UTM. 2003;9:30-37.
  14. Cohen MD, Cooper ML, Piersall K, Apgar BK. Quality assurance: using the exposure index and the deviation index to monitor radiation exposure for portable chest radiographs in neonates. Pediatr. Radiol. 2011;41:592-601. https://doi.org/10.1007/s00247-010-1951-9

Cited by

  1. A Convergence Study on Evaluation of Usefulness of Copper Additional Filter in the Digital Radiography System vol.13, pp.9, 2015, https://doi.org/10.14400/JDC.2015.13.9.351
  2. A Analysis of Effectiveness of Aluminium Filter in the added Compound Filtration by Detective Quantum Efficiency and Image Quality Evaluation vol.15, pp.10, 2015, https://doi.org/10.5392/JKCA.2015.15.10.362